Even if the account number is wrong, the OP will not get it back. I am sorry, but most people in India would never return such an amount. The problem is, OP has to talk through a middleman, which is you, which is why it takes time. The first question would be how OP got this bank account number if this was not from the BC game merchant? Also, is it possible for the merchant to change their account number?

What if the merchant is the scammer here? I think we have seen some scammer merchants before. A lot of people in my country makes deposit via Bkash, Nagad and other local channels and often they get scammed - because the merchant is scammer, not the casino. Now it is up to the casino if they want to investigate the case.